<div class="carousel">
    <div class="wrap">
        <!-- 上一张 -->
        <i class="arrow left" (click)="onChangeSlide('pre')"></i>
        <!-- 插槽 -->
        <ng-content>

        </ng-content>
        <!-- 圆点模板 -->
        <ng-template #dot let-number>
            <i class="dot" [class.active]="number===activeIndex"></i>
        </ng-template>
        <!-- 下一张 -->
        <i class="arrow right" (click)="onChangeSlide('next')"></i>
    </div>
</div>